Clamp



FIG. 1 is a perspective view of a clamp showing my new design;

FIG. 2 is a left side view thereof, the right side view being a mirror image of the left side view;

FIG. 3 is a top view thereof, the bottom view being identical to the top view;

FIG. 4 is a front elevation view thereof; and,

FIG. 5 is a rear elevation view thereof. 

The ornamental design for a clamp, as shown and described. 